Which of the following is a complex sentence? a) harry had to work on the weekend to finish his report b) because harry took a vacation, he worked all weekend, and he finished his report c) because he took four day off from his job , harry had to work on the weekend to finish his report d) harry took four days off his job , so he had to work on the weekend to finish his report

Which sentence is punctuated correctly?  a.under a microscope; the organisms look a bit like ruffled tennis balls they have armored plates that fit together to make a round shape. b.when the water is disturbed; the organisms respond by glowing this makes swimmers look like floating beams of blue light. c.there is a bay in puerto rico that seems to light up at night; the light comes from tiny organisms in the water. d.the luminescence attracts visitors from around the world people are curious to see; this beautiful otherworldly sight.